Research into the roles of peer and friend relationships has been an active area of inquiry for developmental scientists, particularly those studies investigating their role in promoting healthy adolescent development. Strong relationships with peers have been linked to perceived self-worth, high levels of perspectivetaking and prosocial behavior, and decreased risk of emotional and behavioral problems. Only recently, however, has intentional discussion ensued as to the role of peers and friends in more domain-specific areas of adolescent development, particularly as it pertains to religious faith development.

Theories of adolescent development give central importance to the change in the nature of adolescents' relationships with parents and the rising prominence and presence of relationships with peers, especially friends. Important structural and functional differences separate peer relationships from adolescent-parent relationships. For example, an adolescent can relate on restricted levels to a parent (e.g., son or daughter), but the same adolescent must relate to age-level associates according to the dimensions of the peer group and on a dyadic level with particular friends.

There is a distinct structure to adolescent interpersonal relationships. For example, friendship is the experience of having a close, dyadic relation that provides opportunities for loyalty, affection, and intimacy. Alternatively, participation within a peer group is the experience of being liked or accepted more widely by the members of one's peer groups, offering a sense of inclusion. Thus, although friendship and peer groups are conceptually and empirically related, the literature suggests that they each contribute uniquely to an adolescent's social adjustment and development. The resulting discussion will not make qualitative distinctions between peers and friends, but it is noted that influences on adolescent faith development likely do differ according to the nature and structure of the relational system.

As one moves from childhood to adolescence, most developmental and social scientists articulate agreement on the enlargement of one's social contexts beyond the family to include that of peers and friends. During adolescence one becomes immersed in an environment that is defined largely in interpersonal terms, of which its unifying value and power derive from the qualities experienced in personal relationships. As a result, the adolescent becomes acutely aware of the expectations and judgments of significant others. For example, the views of one's peers notably inform both the experience and expression of faith for the youth. For most adolescents, bridging the gap between the parental indoctrination and personal revelation of faith experience are the important contributions made by peers and friends.

Although religious scholars theorize that adolescent peer groups should be expected to play an increasing role in the development of religious faith (especially during the early and middle adolescent stages), conclusions regarding the role of peers and/or friends in adolescent faith development are tenuous at best and completely neglected at worst. Theory and research that do exist focus quite heavily on the transmission model of interpersonal relationships on religiosity; that is, the religious behavior of peers and friends (e.g., peer church attendance) have been found to have at least moderate positive influence on religious practice (e.g., participation in the church youth group and enjoyment of that participation) but less substantial influence on adolescents' religious belief. Thus, peer and friend influence limited to that of providing religious behavior modeling appears to have marginal influence on an adolescent's faith development, and only then in the direction of concurrent religious behavior itself.

In addition to the transmission model of peer influence, at least two other models have been proposed to describe the nature of peer and friend relationships on adolescent faith development, the transaction model and the transformation model. In the first case, the transaction model states that peers and friends not only have the potential to shape an adolescent's own religious behavior and participation, but they also impact the more intrinsic nature of religiosity by way of their reciprocal interaction and religious communication. More than one study has demonstrated that the extent to which one's faith journey is actively shared (i.e., via interaction and dialogue) with and between friends and peers impacts adolescents' experience of God and maturing of faith. Thus, the adolescent seems to be influenced not only by their friends' and peers' modeling of religious behavior but also by the sharing of faith experiences (e.g., frustrations, successes, mutual goals) between an adolescent and his or her friends and peers. A third model, the transformation model, attempts to put into perspective the dynamic nature of both parent and friend relationships and its affect on adolescent faith development. In general, the transformation model suggests that although time spent with parents during the adolescent years steadily declines, the role and influence of peers and friends does not eliminate that of the adolescent's parents. Instead, with specific reference to adolescent faith development, important friendships seem to add to the strength of faith modeling and faith dialogue already initiated and still present within the parent-adolescent relationship. Thus, the transformation is represented by both the widening and deepening in the adolescents' relationship system to include similar-age relationships in addition to those already present with the parent(s). There is growing support for the suggestion that parental modeling and support provide a foundation upon which the adolescent can begin his or her search for meaning through faith. In most cases, however, an adolescent's experience of faith does not normally end with the acceptance of his or her parents' faith. Rather, parents may provide the "necessary" modeling and motivation for the development of faith, but they are rarely "sufficient" in bringing the adolescent to his or her potential in religious belief and commitment. It is more likely that the internalization of beliefs that was initially nurtured by parents evolves to include and be represented by meaningful and deepening friend relationships with which the adolescent can share faith journeys on a more symmetrical and truly reciprocal level. The relationship with "faith-full" friends becomes, then, useful to the adolescent not only as a place to be comfortable with shared beliefs but also as a forum that legitimates the adolescent's own search for individual belief and commitment that was started many years earlier within the context of the parent- child relationship.